| 摘要 |
Disclosed is a folding mechanism of a seat backrest rod (21). A connector (22) there the folding mechanism is rotationally connected to a connection base (12) via a connection pin. An arc-shaped trench (221) which takes the connection pin as a circle centre is formed in an outside surface of the connector (22), wherein one end of the trench (221) is an inclined groove (222) which is smoothly connected to the outside surface of the connector (22). A sliding groove (121) corresponding to the trench (221) is formed in the connection base (12), a positioning block (3) which can slide leftwards and rightwards and inwardly extends out of the connection base (12) is provided in the sliding groove (121), and a pressure spring (4) is provided between the outer end of the positioning block (3) and the connection base (12). When the backrest rod (21) rotates forward to be folded relative to a cushion rod (11), the positioning block (3) is moved out of the trench (221) via the inclined groove (222) and is matched with the outside surface of the connector (22) and then the pressure spring (4) is shrunk; when the backrest rod (21) is unfolded backwards, the positioning block (3) enters the trench (221) via the inclined groove (222) from the outside surface of the connector (22) and then the pressure spring (4) is loosened. This mechanism not only enables the operation of backward rotation of a backrest assembly to be relatively easy, but also avoids forward folding of the backrest assembly due to faulty operation. |
